I’ve had a look around but can’t find a definitive answer.
I’m going to be switching from an apm to pixhawk and plan to fit the diode/capacitor as recommended, however I’ve found various posts saying that it needs a 5.5v, 5.6v, 6v or even 6.3v capacitor
Now, I have quite a few capacitors lying around but the 100uF 220uF and 470uF I have are all 25v. Could one of these be used or can anyone confirm what rating diode (V and W) and capacitor (uF and V) I should be using? Will only be using standard analog servo’s if any at all.
For the Zener I’ve always used the recommended part number (1N5339), which is a 5.6 volt zener. It’s spec’ed as having a max current rating of 865 mA, if that helps.
Use of a capacitor is less clear. Some folks use one also (I don’t) but it’s not suggested anywhere in the wiki that I’ve ever seen. That said, if you want to use a capacitor the specs are pretty loose. You first need a voltage rating that’s higher than the zener output of 5.6 volts, otherwise you’ll blow the cap. I’d wouldn’t be comfortable with anything less than 10 volts, and would probably shoot for 16 - 25 volt rating. The higher voltage rating gains you nothing but a larger safety factor, but as you go up in voltage the size does get larger. The capacitance value is just its ability to absorb “surges” so any of the values you list would be fine. Also the size goes up with capacitance too, so it may come down to what fits. Oh, and pay attention to the polarity of the capacitor so you don’t hook it up backwards. I speak from experience…